Volkswagen Jetta fan draining battery issue, won't turn off on Volkswagen Jetta

Some Volkswagen Jetta owners report experiencing battery drain issues due to the cooling fan not turning off. This problem may stem from a faulty cooling fan relay, which can cause the fan to run continuously. Additionally, defective temperature sensors have been noted as a cause for the fan's constant operation, even when the engine is off. A dirty radiator can exacerbate the situation, leading to more frequent fan operation and excessive battery drain. Some owners also find that a malfunctioning electronic control unit (ECU) sends incorrect signals, causing the fan to run unnecessarily. Lastly, short circuits in the wiring related to the fan relay or control unit can keep the fan running, further draining the battery. It is advisable for affected owners to consult a qualified mechanic to diagnose and resolve these issues promptly to prevent further battery problems.